Incendiary composition for a fin-stabilized kinetic energy projectile

ABSTRACT

An incendiary composition ( 14 ) for a fin-stabilized kinetic energy projectile ( 1 ) which can be arranged in the tail region of the projectile ( 1 ) and, upon impact with a target ( 13 ), penetrates the target ( 13 ) as a separate unit behind the penetrator ( 2 ) of the kinetic energy projectile ( 1 ). To reach the objective of a high destructive effect caused by the incendiary composition ( 14 ) within a target ( 13 ), despite a small volume and a low mass, and to ensure that the incendiary composition is ignited securely by the shock waves generated upon impact, according to the invention, a titanium sponge is used as the incendiary composition ( 14 ), with an epoxide resin or a polyester resin used as a binder.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based on and claims the priority date of GermanApplication No. 101 40 600.2, filed on Aug. 18, 2001, which isincorporated herein by reference.

BACKGROUND OF THE INVENTION

The invention relates to an incendiary composition for a fin-stabilizedkinetic energy projectile, which can be installed in the tail region ofthe projectile and, upon impact with the target, penetrates the targetas a separate unit behind the penetrator of the kinetic energyprojectile.

Fin-stabilized kinetic energy projectiles with incendiary compositionsarranged in the tail region of the projectile are described, forexample, in German Patent Applications DE 199 48 708.1 and DE 199 48710.3. With kinetic energy projectiles of this type, the tracer setnormally used is replaced with the incendiary composition to achievethat the kinetic energy projectile developing a considerable incendiaryeffect when hitting semi-hard targets (e.g., armored personnel carrierswith relatively thin armor). Without such an incendiary composition, thepenetrator of the kinetic energy projectile would simply fly through thesemi-hard target, essentially without causing any destruction, and wouldcreate a hole matching the maximum projectile diameter in the armor.

To be sure, reference DE 199 48 710.3 already discloses that theincendiary composition arranged in the tail section of the kineticenergy projectile can be selected such that it will be initiated by theshock wave generated during the impact with a corresponding target.However, this reference does not offer further details concerning theconcrete design of such an incendiary composition.

Incendiary compositions consisting of a metal sponge and an organicbinder are known from reference DE-AS 29 01 517, wherein it ispreferable if a metal sponge consisting of zirconium or hafnium and abinder of poly tetrafluoroethylene are used. Experiments conducted bythe applicant have shown that these known incendiary compositions cannotbe initiated optimally by shock waves, in particular if only relativelysmall amounts of the respective incendiary composition are used, as isthe case with incendiary compositions for kinetic energy projectilesthat replace the tracer sets.

SUMMARY OF THE INVENTION

It is the object of the invention to provide incendiary compositions forfin-stabilized kinetic energy projectiles, which cause considerabledestruction in a target despite having a relatively small volume and lowmass and which are securely ignited by the shock waves generated uponimpact with the target.

The above object generally is achieved according to the presentinvention in that a titanium sponge is used as the incendiarycomposition with epoxide resin or polyester resin used as a binder.Since the incendiary composition does not contain an oxygen carrier, itis relatively insensitive. Several advantageous embodiments aredisclosed.

Upon impact with the target, the titanium sponge particles are heated tothe ignition temperature and continue to burn intensively when theparticles are released and come in contact with the oxygen in the air.

Experiments have shown that the relatively brittle titanium spongebecause of its low ductile quality is considerably more suitable for anincendiary composition than ductile materials such as zirconium powder,magnesium powder or aluminum powder. In addition, the incendiarycompositions according to the invention can also set on fire hard toignite oils (such as diesel or hydraulic oil).

Another advantage of the incendiary compositions according to theinvention is that during the normal state, they behave in the samemanner as an inert material and can be ignited only with an extremelystrong impact. Thus, the projectile can be handled safely even if thetarget is missed, provided the incendiary composition is not damaged.

The incendiary composition of a first advantageous embodiment of theinvention consists of a mixture of 85 to 96 weight % titanium sponge and4 to 15 weight % of the epoxide resin or polyester resin, and has adensity between 1.7 and 2.8 g/cm³.

To increase the energy content (increase in the enthalpy of combustion),it has proven advantageous if 10 to 20 weight % of boron powder aremixed into the incendiary composition, wherein the grain size of theboron powder should preferably be ≦10 μm. The incendiary composition ofa second embodiment is therefore composed of a mixture of 65 to 86weight % titanium sponge, 4 to 15 weight % of an epoxide resin orpolyester resin and 10 to 20 weight % of boron powder, wherein thedensity of the incendiary composition is again between 1.7 and 2.8g/cm³.

To achieve a maximum incendiary effect in the crew compartment of anarmored vehicle of this type, it has proven effective if the grain sizerange for the titanium sponge is selected such that 30% of the titaniumsponge particles have a grain size larger than 450 μm and 70% have agrain size smaller than 450 μm.

Additional details and advantages of the invention follow from the textbelow and the exemplary embodiments explained with the aid of Figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 2 are, respectively, a longitudinal section view through akinetic energy projective containing an incendiary composition accordingto the invention, before and after the impact with an armored target.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In FIG. 1, the number 1 refers to a large-caliber fin-stabilized kineticenergy projectile, for example as fired from tank cannons. The kineticenergy projectile 1 comprises a penetrator 2 and a guide assembly 3 thatis attached to the rear of the penetrator 2. The guide assembly 3essentially consists of a sleeve-type guide assembly carrier 4 withstabilizer fine 5 arranged on the outside and a recess 7 that extends inthe direction of the longitudinal axis 6 of the kinetic energyprojectile 1 and is closed off by this penetrator on the side or endfacing the penetrator 2.

The tail region 8 of penetrator 2 extends into a front partial region 9of the recess 7 and is non-positively connected to the guide assemblycarrier 4, for example, via a threaded connection 10.

A case 12, which contains an incendiary composition 14 that is ignitedonly when impacting with a target 13 (e.g., a tank) (FIG. 2), is locatedinside a rear partial region 11 of the recess 7, which adjoins the frontor forward partial region 9 on the tail side. The incendiary composition14 is arranged inside the recess 7, such that it can be displaced in thedirection of longitudinal axis 6 of the kinetic energy projectile 1 uponimpact of the projectile on a target.

If the kinetic energy projectile impacts the relatively thin wall 15 ofthe slanted target 13 (e.g. at an angle of 60°), the penetrator 2initially penetrates this wall 15 mostly unhindered. As soon as theguide assembly 3 hits the wall 15, it is separated from the penetrator 2owing to its large diameter and the connected resistance and eitherremains in the wall 15 of target 13 or continues to fly withconsiderably reduced speed as compared to the penetrator 2. In theprocess, the stabilization fins 5 of the guide assembly 3 splinter andthe case 12 of the incendiary composition 14 is torn, at least in somesections.

As a result of its mass inertia, the torn case 12 flies from theopened-up opening 16 of recess 7 in the guide assembly carrier 4 behindthe penetrator 2 and is smashed, e.g., at the rear wall or on objectslocated inside the tank, thereby releasing the incendiary composition.The incendiary composition reacts with the oxygen in the air, so that arain of hot sparks is sprayed far and results in considerable incendiaryeffect.

According to a first embodiment of the invention, the incendiarycomposition is comprised of 85-96 weight % titanium sponge and 4-15weight % of an epoxide resin or a polyester resin, and the density ofthe incendiary composition is in the range of 1.7 to 2.8 g/cm³.

According to a second embodiment of the invention, boron powder is addedto the incendiary composition that is now comprised of 65-86 weight %titanium, 4-15 weight % of an epoxide resin or a polyester resin, and10-20 weight % of boron powder, and the density of the composition is inthe range of 1.7-2.8 g/cm³. Preferably, the boron powder has a grainsize equal to or less than 10 μm. The boron increases the combustionenergy of the incendiary composition so that a correspondingly highereffect is achieved in the target because of the increased heat.

The following specific mixtures, for example, are advantageously usedfor the two embodiments of the incendiary compositions:

-   -   1. 96 weight % titanium sponge (grain size range: 30% larger        than 450 μm; 70% smaller than 450 μm) 4 weight % epoxide resin        (Araldit) mixture is compressed to a density of 2.5 g/cm³.    -   2. 80 weight % titanium sponge (grain size range: 30% larger        than 450 μm; 70% smaller than 450 μm); 5 weight % epoxide resin        (Araldit) 15 weight % boron powder (grain size range: ≦10 μm)        mixture is compressed to a density of 2.5 g/cm³.

Preferably, in both exemplary embodiments, the grain size range for thetitanium powder is such that substantially 30% of the titanium spongeparticles have a grain size larger than 450 μm and 70% have a smallergrain size.

While this invention has been particularly shown and described withreference to preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the spirit and scope of theinvention, as defined by the appended claims.

1-2. (canceled)
 3. An incendiary composition for a fin-stabilizedkinetic energy projectile, which can be arranged in the tail region ofthe kinetic energy projectile and, upon impact with a target, enters thetarget as a separate unit behind the penetrator of the kinetic energyprojectile, said incendiary composition comprising: 65 to 86 weight % oftitanium sponge, 4 to 15 weight % of an epoxide resin or a polyesterresin, and 10 to 20 weight % of boron powder; and wherein the density ofthe incendiary composition is between 1.7 and 2.8 g/cm³.
 4. Anincendiary composition according to claim 3, wherein the incendiarycomposition consists essentially of 80 weight % titanium sponge, 5weight % epoxide resin and 15 weight % boron powder, and has a densityof 2.5 g/cm³.
 5. An incendiary composition according to claim 4, whereinthe boron powder has a grain size of ≦10 μm.
 6. An incendiarycomposition according to claim 3, wherein the boron powder has a grainsize of ≦10 μm.
 7. An incendiary composition according to claim 6,wherein the grain size range for the titanium sponge is such that 30% ofthe titanium sponge particles have a grain size larger than 450 μm and70% have a grain size smaller than 450 μm.
 8. An incendiary compositionaccording to claim 5, wherein the grain size range for the titaniumsponge is such that 30% of the titanium sponge particles have a grainsize larger than 450 μm and 70% have a grain size smaller than 450 μm.9. An incendiary composition according to claim 4, wherein the grainsize range for the titanium sponge is such that 30% of the titaniumsponge particles have a grain size larger than 450 μm and 70% have agrain size smaller than 450 μm.
 10. An incendiary composition accordingto claim 3, wherein the grain size range for the titanium sponge is suchthat 30% of the titanium sponge particles have a grain size larger than450 μm and 70% have a grain size smaller than 450 μm. 11-13. (canceled)